Terthreutis subrectangulus, Naik & Shashank, 2024

Naik, Santhosh & Shashank, P. R., 2024, Discovery of two new species and three new records of the tribe Archipini (Lepidoptera: Tortricidae) from India, Zootaxa 5492 (3), pp. 409-420 : 415-419

Terthreutis subrectangulus sp. nov. Shashank & Santhosh

( Fig. 1F , 2E , 3I–J , 5G–H )

Type locality: India (Umiam, Meghalaya)

Holotype: INPC

Diagnosis. Terthreutis subrectangulus sp. nov. is closely related to Terthreutis chiangmaiana Razowski, 2008 in adult morphological resemblance but differs in male genitalia characters. Terthreutis subrectangulus has transtilla incomplete, valva subrectangular, and smooth phallus without any serration whereas T. chiangmaiana has transtilla complete and continuous, valva rounded, and serrated phallus with the presence of some denticles in the distal portion. Also, it is found that the transtilla is non-continuous or incomplete with two sclerotized lobes and this type of transtilla is present in some species of Terthreutis such as T. bipunctata , T. orbicularis , T. xanthocycla , T. sphaerocosma and T. series . However, there are thirteen species described worldwide ( Buchsbaum & Chen, 2013; Gilligan et al., 2018), out of which three species have been described from India: T. argentea , T. bulligera and T. sphaerocosma ( Pathania et al., 2020) . However, most of the species of Terthreutis are different but present some elements similar to the new species for example an incomplete transtilla, elongated and well sclerotised uncus, gnathal arms long and wide and well sclerotised sacculus about as long as 1/2 of the length of valva. This study adds one more species to the world fauna of Terthreutis and increases the number of Indian species to four.

Description. Head. Ocellus small, brown compound eyes. Head dusted cream white, face cream white. Vertex and dorsal part of frons clothed with long pale cream white rough, upwardly projected scales. Ventral part of frons region covered with small, flat, upwardly raised pale ochreous white scales. Labial palpi slender, clothed with forwardly projected whitish cream scales; first segment short, cream white, tinged with brownish cream; second segment curved, brownish white, interspersed with pale ochreous along dorsal margin from base to near apex; small third segment, porrect with large ochreous white scale. Antenna filiform, pale ochreous white with short cilia. Chaetosemata present.

Thorax. Pronotal collar, tegulae, mesonotum, and posterior crest brownish cream mixed with ochreous yellow scales; legs unmodified, middle legs with a pair of tibial spurs; hind tibia covered with dense, cream white scales interspersed with light cream scales, inner margin with tuft of whitish cream scales. Wings: Forewing (wingspan 20 mm; n= 5) uniformly broad, costa tinged ochreous, termen weakly oblique, gently sinuate; cream brownish ground color; tornal spot small, brown accompanied by more anterior cream brown elongate blotch; postmedian blotch rounded, brownish cream; some brown dots in apical and terminal area. Hindwing yellowish cream with concolor cilia along the apical and anal margin. Wing venation: Forewing with all the veins separated beyond the discal cell, R4 and R5 stalked, M3 and CuA1 arched basally, CuP indistinct. Hindwing Sc reach up to Rs and M1 stalked, M3 and CuA1 stalked, CuP distinct.

Abdomen. Clothed with yellowish cream. Male genitalia: Uncus long, slender, strongly scelerotised, uniform width narrow towards apex; tegumen broad, rectangular, well seclerotised with strong shoulders; socius not prominent; gnathos strong with small lateral prominence and large terminal lobe; gnathal hooks highly sclerotized, from apex of tegumen shoulder; valva large, subrectangular, symmetrical, lightly sclerotised with minute hairs; transtilla incomplete, with two sclerotised lobes; sacculus strongly sclerotized, uniform width, reach 1/2 of valva; cucullus membranous with tufts of hairs; juxta medium, dumbbell- shaped with broad and rounded base; anellus cup shaped and fused with phallus; vinculum medium well sclerotized. Phallus simple, long and slender with uniform width. No cornuti detected.

Female. Unknown.

Material studied. India: Meghalaya: Ri Bhoi: CPGSAS, Umiam (25°03’22’’N, 91°54’42’’E, 1520 MSL), 2♂, 17.iii.2021, Mercury vapour lamp coll. Santhosh Naik G & Sunil ; India: Mizoram: Kolasib (24°11’51’’N, 92°41’40’’E, 493m), 1♂, 10.ii.2020, Mercury vapour lamp coll. Niranjana G N & Tahseen R H; Mizoram: Kolasib (24°11’51’’N, 92°41’40’’E, 493m), 1♂, 11.ii.2020, Mercury vapour lamp coll. Niranjana G N & Tahseen R H; India: Himachal Pradesh: Hamirpur: Neri (31°40’56’’N, 76°29’15’’E, 733 MSL), 1♀, 19.xi.2019, Mercury vapour lamp coll. Shivanshu G ; genitalia slide no. L00050946 (♂).

Etymology. The new species Terthreutis subrectangulus sp. nov. is named after the subrectangular shape of the valva, which is distinct from all other described species of Terthreutis .

Distribution. India (Himachal Pradesh, Meghalaya, Mizoram)

Remarks. Genus Terthreutis is described by Meyrick (1918), and species of the genus were studied by Kawabe et al. (1992) and Razowski (2008). Terthreutis subrectangulus sp. nov. resembles Terthreutis chiangmaiana Razowski, 2008 in the appearance, but differs in the male genitalia, transtilla incomplete, valva subrectangular, and phallus is smooth without any serration; whereas in T. chiangmaiana the transtilla is complete and continuous, the valva is rounded, and the phallus is serrated with the presence of some denticles in the distal portion.

Figures

FIGURE 1. Dorsal habitus illustrations. A. Choristoneura ribhoiensis sp. nov. (holotype, male); B. Clepsis laetornata (male); C. Clepsis laetornata (female); D. Diplocalyptis ferruginimixta (male); E. Diplocalyptis operosa (male); F. Terthreutis subrectangulus sp. nov. (holotype, male). Scale bar = 2 mm.

FIGURE 2. Labial palpi. A. Choristoneura ribhoiensis sp. nov. (holotype, male); B. Clepsis laetornata (male); C. Diplocalyptis ferruginimixta (male); D. Diplocalyptis operosa (male); E. Terthreutis subrectangulus sp. nov. (holotype, male). Scale bar = 0.5 mm.

FIGURE 3. Wing venation; Choristoneura ribhoiensis sp. nov. (holotype, male) (A. Forewing, B. Hindwing); Clepsis laetornata (C. Forewing, D. Hindwing)); Diplocalyptis ferruginimixta (E. Forewing, F. Hindwing); Diplocalyptis operosa (G. Forewing, H. Hindwing); Terthreutis subrectangulus sp. nov. (holotype, male) (I. Forewing, J. Hindwing). Scale bar = 1 mm.

FIGURE 5. Diplocalyptis ferruginimixta (A. Male genitalia, B. Uncus, C. Phallus); Diplocalyptis operosa (D. Male genitalia, E. Uncus, F. Phallus); Terthreutis subrectangulus sp. nov. (holotype, male) (G. Male genitalia, H. Uncus & Socii). Scale bar A, D, G= 0.5 mm; B, C, E, F, H= 0.1 mm.